Diagnosis and outpatient management of Gitelman syndrome from the first trimester of pregnancy

A Case of Recurrent Gestational Hypokalemia Due to an Exaggerated Physiological Response to Pregnancy: The Importance of Using Pregnancy-Specific Reference Ranges

Hypokalemia in pregnancy can occur secondary to hemodilution of pregnancy, physiological changes during pregnancy, or other pathological conditions. It should be investigated the same way as in non-pregnancy with particular emphasis on the importance of using pregnancy-specific reference ranges when interpreting clinical laboratory test results. Here, we present a case of a woman who had late-trimester gestational hypokalemia requiring potassium supplementation affecting four consecutive pregnancies. We thought that there was accompanying hypomagnesemia and hypobicarbonatemia in previous pregnancies, so we suspected a form of renal tubular dysfunction exacerbated by pregnancy. Subsequent investigation and the use of pregnancy-specific reference ranges revealed that this was an exaggerated physiological response to pregnancy.

Molecular Basis, Diagnostic Challenges and Therapeutic Approaches of Bartter and Gitelman Syndromes: A Primer for Clinicians

Gitelman and Bartter syndromes are rare inherited diseases that belong to the category of renal tubulopathies. The genes associated with these pathologies encode electrolyte transport proteins located in the nephron, particularly in the Distal Convoluted Tubule and Ascending Loop of Henle. Therefore, both syndromes are characterized by alterations in the secretion and reabsorption processes that occur in these regions. Patients suffer from deficiencies in the concentration of electrolytes in the blood and urine, which leads to different systemic consequences related to these salt-wasting processes. The main clinical features of both syndromes are hypokalemia, hypochloremia, metabolic alkalosis, hyperreninemia and hyperaldosteronism. Despite having a different molecular etiology, Gitelman and Bartter syndromes share a relevant number of clinical symptoms, and they have similar therapeutic approaches. The main basis of their treatment consists of electrolytes supplements accompanied by dietary changes. Specifically for Bartter syndrome, the use of non-steroidal anti-inflammatory drugs is also strongly supported. This review aims to address the latest diagnostic challenges and therapeutic approaches, as well as relevant recent research on the biology of the proteins involved in disease. Finally, we highlight several objectives to continue advancing in the characterization of both etiologies.